1. Field of the Invention
The present invention relates to a method used by a robot for localization and map-building, and more particularly, to a method used by a mobile robot for simultaneous localization and map-building (SLAM).
2. Description of Related Art
In order for a robot to navigate through the non-trivial surroundings, the robot must localize itself and build a map of its surroundings. The map as built makes it possible for the robot to plan its path, manipulate an object, or communicate with humans, etc.
In order to navigate through unknown surroundings, a robot has to build a map while localizing itself. However, since the robot localizes itself and builds a map by using sensor data having noise, there is difficulty in the calculation.
Localization means understanding of the absolute location of a robot in its surroundings by using sensor information, beacons or natural landmarks, etc. Since there are several sources of error in localizing the robot (a wheel slipping on the ground, a change in the diameter of the wheel, etc.) during the navigation of the robot, the error requires a correction.
Map-building models the surroundings by observing natural or manmade landmarks based on the sensor data. Such modeling makes it possible for the robot to plan its path. In order to model complex surroundings, only when localization is guaranteed, can a reliable map be built. Therefore, a method of simultaneously performing localization and map-building within a specified short time is required.